Safety device for elevators.



PATENTED JULY 24, 1906.

I D. F. .LBPLEY. SAFETY DEVICE FOR ELEVATORS.

- APPLICATION EILEE APB-3.1906.

2 SHEETS-SHEET 1.

[NI/ENTOR A TTOR/VE VS 1m: murals PETERS co., WASHINGTON, 0.1:.

PATENTED JULY 24, 1906. D. F. LEPLEY.

SAFETY DEVICE FOR ELEVATORS.

APPLIOATIOR IILED APR. 3. 1906.

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[NI ENT R o ings. W n mine-cages and elevator-car's generally guides, the gripping force being distributed UNITED STATES PATENT OFFICE.

SAFETY DEVICE FOR ELEVATORS- Specification of Letters Patent.

Patented July 24, 1906.

Application filed April 3, 1906. Serial No. 309,641.

To all whom it may-concern.-

Be it known that I, DANIEL F. LEPLEY, a citizen of the United States, residing at Connellsville, in the county of Fayette and State of Pennsylvania, have invented a new and useful Safety Device for Elevators, of which the following is .a specification.

This invention relates to safety appliances for elevators, and while applicable to elevators in general is intended more especially to be used in connection with mine-cages.

The principal object of the invention is to provide a safety device in which wedge clutch-blocks are arranged to engage with the opposite sides of the guide rails or sills that run from bottom to top of the shaft and to so arrange these clutch-blocks as to obtain a very extensive clamping-surface that will not only arrest the downward movement of the cage, but will prevent injury to the over such a large area of the strips as to prevent serious mutilation or injury to said strips.

A still further object of the invention is to provide an improved means for controlling the operation of the safety clutching-blocks.

With these and other objects in view, as will more fully hereinafter appear, the invention consists in certain novel features of construction and arran ement of parts, hereinafter fully describe illustrated in the accompanying drawings, and particularly pointed out in the appended claims.

In the accompanying drawings, Figure 1 is a sideelevation of the upper portion of a mine-cage provided with safety clutching- -blocks constructed and arranged in accordance with'the invention. Fig. 2 is an elevation looking at right angles to Fig. 1. Fig. 3 is a plan view of the top of the cage. Fig. 4 is a detail perspective view of one of the clutching-block guiding and supporting devices, showing one of the clutch-blocks in position. Fig. 5 is a similar view of one of the clutch-blocks detached.

Similar characters of reference are employed to indicate corresponding parts throughout the several figures of the drawser'iou's' accidents frequently occur from breakage of the hoistingcable, and many forms of safety devices have been employed for arresting downward movement of the cage, most of which aim to grip or otherwise Y engage with the guide-strips on the shaft, the latter in many cases being in the form of a toothed rack and the cage being provided with toothed blocks which may be projected into engagement with the rack or racks. It has also been proposed to employ pivotallymounted cam-shaped or eccentric clam s for gripping the opposite side of the gui estrips and to employ wedge-shaped blocks which are forced into contact with the opposite sides of the strips to check the downward movement of the cage. In carrying out the present invention care is taken to distribute 'the gripping effect over a relatively large area, so that the strips will not be injured to such an extent as to interfere with their ordinary use, and the wedge blocks are so mounted and so related that they cannot be accidentally disengaged, and at the same time the controlling mechanism by which the wedges are set into operation is simplified and is so arranged as to insure simultaneous operation of all of the wedges.

The cage A may be of any ordinary construction, so far as the suspension members, flooring arrangements, and other parts are concerned, and the guides B are shown as formed of wood, this being the material commonly employed for the purpose.

In constructing the cage angle-bars 10 are arranged at each side, the bars being disposed in pairs and spaced from each other to receive the wooden guide-strips B. These bars have their inner webs riveted to lates 11, Which-serve to maintain them in ed relation to each other, and to the inner face of the plate 11 are secured angle-bars 12. As a rule'it is found more convenient to rivet directly through the webs of the angle-bars and the intervening plate 11, as shown. To the inner face of each angle-bar 12 is riveted the lower end of a heavy plate 13, that extends upward above the'top of the cage proper. The lower portions of these plates 13 are connected by cross-bars 14, formed of heavy metal, and these form the main suspensionbars of the cage. At the central portion of these two bars is arranged a yoke 15, the lower edges of which are provided with flanges 16, that fit under the cross-bars, while the upper central portion of the yoke is provided with an opening for the passage of a suspension-rod 17. The lower end of this rod carries a collar or disk 18, held in place by nuts 19, and surrounding the rod is a compression-spring 20, on which the weight of the cage is suspended, the spring yielding to some extent as the cage starts on its upward movement, and thus taking up the jar at starting. The upper end of the suspensionrod is coupled by a bar 21 to a ring 22, to which-the lower end of the hoisting-cable is secured, and depending from this ring are safety-chains 23, the lower ends of Which are connected to pins or bolts that pass through the cross-bars 14 and the plates 13. The up- .per portions of the plates 13 are connected together by transversely-extending anglebars 25, which hold the plates in rigid alinement.

The upper ends of the plates 13 extend within or between the rear vertical webs 26 of heavy castings 27, there being one of said castings at each side of the upper portion of the cage. These castings are firmly secured by rivets or bolts to the plates 13, and as a further precaution heavy pins 28 are passed through the webs 26 and plates and form the lower connections of auxiliary safety-chains 29, that extend up to the hoisting member.

The upper face of each of the castings 27 is provided with a recess to receive the guidestrip B, and the walls of this recess are tapermg, being arranged on lines that gradually diverge from the top to the bottom of the casting. Each of the walls of the recess is provided with a groove 30, the bottom wall of which is parallel with the inclined wall of the recess. In these grooves fit the reduced shanks 31 of the wedge clamping-blocks 27, the parallel walls of the groove holding each block from lateral play, while outward movement from the strip is limited by engagement of the inclined face of the block with the inclined wall of the recess. In each of the shanks or ribs 31 is formed an elongated slot 33 for the passage of a bolt or pin 34, which is much smaller in diameter than the Width of the slot, so that it is not subjected 'to any strain during the operation of the clampingblock, but merely serves to retain said 'block in position and to exercise a camming effect in drawing the blocks outward away from the guide-strip during the ordinary operation of the cage.

The upper ends of the blocks are provided with openings 36 for the reception of the inner ends of levers 37, that are pivoted on small brackets 38, carried by the plates 13. The levers all extend inward toward the center of the cage and are all connected together by a heavy pin or bolt 39, the central portion of which is rigidly secured to the extensionrod.

One of the principal di-fliculties found in "safety devices of this general class is that where sharp teeth are employed on the gripping-blocks the wooden guides at the sides of the elevator-shaft will be destroyed, and considerable expense is entailed each time the elevator is tested. In order to overcome this the weight of the latter will hold the spring 2O compressed, and the outer ends of the levers 37 will be forced down, so that the wedge blocks will be moved outward by the engagement of the walls of the slots 33 with the pins 34. Should the hoisting-cable or the connecting-rod 21 break, the sprin 20 immediately pulls the suspensionro 17 down and raises theouter ends of all of the le vers 37. The inclined faces of the wedge blocks then ride against the inclined walls .of

the recesses of blocks .27, and the faces of the wedge blocks are thrust against the-opposite sides of the guide-strips B. It will be noted that the wedge blocks are of a width equal to the width of the walls of the recesses and the clutching-faces of the blocks are of considerable length, so that the area of the blocks will be such as to distribute the shock of the clamping effect and bring the cage to a stop with out serious injury to the guide-strips. The area of the blocks is of course proportioned to the weight of the cage and the loads which the cage is intended to carry.

Having thus described the invention, what is claimed is- 1. In a safety device for elevators, blocks arranged at each side of the cage and provided with recesses for the l assage :of the guide strips or sills, the opposite walls of the recesses being disposed on convergent lines, each wall being centrally grooved throughout its length, wedge blocks having their outer faces tapered and bearing against said convergent walls, each block being provided with a rearwardly-ext'ending rib fittin within the groove, means under thecontroIof the hoisting-cable normally holding the wedge blocks in inoperative position, and means for connecting the wedge blocks to the main blocks.

2. In a safety device for elevators, a block arranged at each side of the cage and each provided with a recess for the passage of the gin'de-strip, the opposite wallsof therecesses being convergent, and wedge blocks having inclined outer faces bearing against suchconvergent walls, the rear faces of the wedge blocks being ribbed, and the main block being grooved for the reception of the ribs, a pin and cam slot connection between the rib and main block for moving the Wedge blocks outward from the strip, and means under the control of the hoisting-cable for permitting operative movement of said wedge blocks.

3. In a safety device for elevators, a block arran ed at each side of the cage and each provi ed with a recess for the passage of the 0 guide strip or sill, the opposing walls of said recess being convergent and each Wall having a vertical groove, wedge blocks having inclined rear faces fitting against the convergent walls and provided with rearWardly-extended ribs that enter the grooves, said ribs having cam-slots, the walls of Which are parallel with the convergent walls of the recess, ins extending through said slots, the slots being of sufficient Width to avoid pressure on the pins, and means under the control of the hoisting cable normally holding the wedge blocks in inoperative position.

4. In a safety device for elevators, a block arran ed at each side of the cage and each provi ed with a recess for the passage of the guide strip or sill, the opposing Walls of said recess being arranged on convergent lines, wedge blocks having their inner faces bearing against said convergent walls, the

up er ends of said wedge bloc-ks being extended above the top of the main blocks, a hoisting device including a suspension-bar at the cen ter of the cage, pins extending from the suspension-bar, a spring surrounding the suspension-bar, and subjected to the weight of the cage under normal conditions, and a plurality of levers extending from the Wedge blocks to the pins, all of said levers being operated by the spring on breakage of the hoisting means.

n testimony that I claim the foregoing as my own I have hereto aflixed my signature in the presence of two Witnesses.

DANIEL F. LEPLEY. Witnesses:

-WILLIAM H. SOISSON H NRY J. BOSLETT. 

